Meteor 3 data coverage Meteor 3 was in a polar drifting orbit with a precession period of 212 days, leading to near-terminator observing conditions every 106 days. The Meteor -3 TOMS data have been screened to exclude measurements taken when the satellite was flying along the terminator. Many of the measurements made near the terminator were at very high solar zenith angles and should not be used because of decreased accuracy. For the first year data are restricted to local equator crossing times (LECT) of 9AM to 3PM because aerosols from Pinatubo were present. By late 1992 aerosol levels were down and LECT 8AM to 4PM could be used. year coverage screened / unscreened 1991 08/22 - 09/02 65/130 10/26 - 12/17 1992 02/09 - 04/02 188/356 05/26 - 07/17 08/31 - 11/09 12/16 - 12/31 1993 01/01 - 02/24 258/364 04/01 - 06/10 07/17 - 09/25 10/31 - 12/31 1994 01/01 - 01/09 220/349 02/14 - 04/25 06/01 - 08/10 09/15 - 11/24